bog from stop, holley 1945 1bbl

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mopar56

mopar56

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so short story version, ( long version, follow threads in slant six section under " holley 1bbl flooding") this carb has been off and on the car for a rebuild and series of adjustments several times, anyway for the most part, the car runs well now, choke works fine, idles well, only one more instance of flooding, but the car, ( 74 duster 225 1bbl fed emission) bogs from stop if you tromp on it, gradual acceleration is ok and tromp while cruising say down into passing ok, but off the line if you dont back out of the pedal it will stall, I have the pump adjustment exactly where the kit instructions say for it to be, ( 3/4" from vacuum casting to outer edge of pump rod hole), and the mixture screw is about 3 1/2 turns out I have tried winding out the mixture and I have tried opening up the loop on the pump rod will little improvement, I doubt its the fuel pump as it works fine under all other loads, any ideas?
 
Check to make sure that you're getting a good shot from the accelerator pump.


With the car off, look down the carb and cycle the linkage and make sure that you get a good squirt of gas for the stroke of the linkage.
 
There is a check ball in the accelerator pump feed, where it gets fuel into the accelerator pump chamber from the bowl. This has to seal when you activate the pump or the fuel will just flow back into the bowl. That may not be sealing right for hard accelerator pump shots and letting enough leak back so that you do not get a good shot; it could be adequate for gentle accelerations where the accelerator pump shot is not needed as much.

Take apart the bowl and remove the metering block that includes accel pump gasket; the check ball is in the metering block behind the inlet port for the accelerator pump. You can test the check ball operation by finding the rebuild video on the Mike's Carburator site for the Holley 1945; they also tell you how to re-seat the check ball to make it seal well.

While this is off, check the small port in the carb body where the accelerator pump feeds fuel into the main venturi's; blow though that with a vaccuum hose held sealed on that port and see if you hear air coming out in the carb throat. And also shoot some carb cleaner through the port and see it come in the throat.

BTW, the idle mixture screw is way too far out for everything to be right.. are you doing this to try to mitigate the bog?
 
as far as timing goes, the motor pings so if anything I would think it too far advanced which should give better acceleration? its at 2.5 de btdc, spec I believe, it dose seem to squirting fuel ok, ( it dose have a new accelerator pump), the way you were talking about removing the bowl and metering block are you sure your thinking of the 1945, its not like the 2bbl carbs, you have to remove the top half to access the bowl/float, how ever there is a check valve in the bowl that has a small rectangular plug above it under the top gasket, I put it in during the rebuild however I have had the carb apart so many times its possible maybe it came out?
 
I recently put in a 1945 (NOS ) into my 75 Swinger (I also removed the 1920). I am currently having the exact same problem you are: bogs down when you give it a healthy push of gas after stopping-having to tender foot it after a sharp turn.otherwise the car drives and idles great. Because my carb was never used I put it in without doing a rebuild. I now think that was a mistake. Soon I'm gonna pull the carb back out and do a rebuild. I'm fairly confident that all my vacuum is working properly. I checked my air cleaner carb vacuum connections. I have done the fuel line mod. I have also noticed that every time I drive the car for 10 minutes or more and stop - the next time I start it I have to do a hot start - pedal slightly down, hold it until a little after it turns over and then release. Def frustrated.
 
well I have narrowed it to one of two things..when I rebuilt mine I removed the small factory set screw on the top of the carb,( under the welsh plug) and I am not sure exactly where it should be set back to as there are no specs for it, some say all the way in? but I know as I started to remove it it did seem as if it wasnt all the way in so I started counting turns, I believe it was two and a half out but not sure I have been experimenting with different positions but havnt noticed a lot of difference, also when I was haveing some flooding problems I adjusted the accelerator pump linkage, I may have it open too far and I might just try closing the "loop" a bit to see if I get more squirt, I will post more if it improves, maybe let me know what you find with yours, maybe you just have a dried up accelerator pump cup as yours was NOS?
 
check to make sure you got the RIGHT accelerator pump they make 3 for this carb . the notch on the shaft is in different place on each. some will only pull about a 1/8 of an inch I had this problem on my newly rebuilt one from the carb shop ,It was put on a 350 Chevy and tested before they shipped it. and you could smell fresh gas in it.( don't know how they missed it)
 
Well, my situation changed for the better when i pulled out the old Champion spark plugs and put in fresh NGK plugs. They were do for a change but I did not expect my problems to go away instantly. I was sure that it was a carb/vacuum problem. My Swinger no longer hesitates, stumbles or stalls.
 
i think the trouble is that the idle jet is to small. in that carb that jet is VERY hard to get to. i have done it. but the best thing to do is get a presmog carb. or get a cartter carb that you can get to the idle jet easier. most of the time the idle is about .032 - .035 inch. what ever the size of the one you have is make it .001 - .002 inch bigger. with idle jets a little is a LOT.
 
OK I just read this which one is the idle jet?, I had this completely apart, I do a lot of marine carbs and ALWAYS COMPLETELY disassemble them so I am pretty certain I would have removed it
 
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